For this problem, we use the Hess' Law.
ΔHrxn = ∑(ν*Hf of products) - ∑(ν*Hf of reactants)
The ν represents the corresponding stoichiometric coefficients of the substances, while Hf is the heat of formation. For pure elements, Hf = 0.
Hf of Al₂O₃ = <span>−1676.4 kJ/mol
</span>Hf of Fe₂O₃ = <span>-826.0 kJ/mol
Thus,
</span>ΔHrxn = 1*−1676.4 kJ/mol + 1*-826.0 kJ/mol
<em>ΔHrxn = -2502.4 kJ/mol</em>
Answer:
So, for 1 I am most certain it has to be Organized so C. And for 2 that would be true if my brain isn't failing me- I hope this helps!
Explanation:
Answer:
Option B, When the cell needs to move a compound against its concentration gradient.
Explanation:
A cell uses active transport when it has to transport substances against the concentration gradient across its membrane.
In active transport additional energy is used (generally provided by energy molecules like ATP) to push the substance across any membrane from low concentration side to high concentration side.
Option B is correct
Answer: The empirical formula is 
.
Explanation:
Mass of C = 1.71 g
Mass of H = 0.287 g
Step 1 : convert given masses into moles.
Moles of C = 
Moles of H = 
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C =
For H =
The ratio of C: H = 1: 2
Hence the empirical formula is .
Matter is classified into two groups: Pure Substances and Mixtures.
